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<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    function Person(name, age) {
      this.name = name;
      this.age = age;

      return 1
    }
    Person.prototype.do = function () {
      console.log("学习 react")
    }



    //手写new的函数
    function myNew(constr, ...arg) {
      //1.创建一个对象
      const obj = {};

      //2.调用构造函数把构造函数的this指向我们创建的对象
      const re = constr.apply(obj, arg)

      //3.把obj的隐式原型指向构造函数的原型对象
      obj.__proto__ = constr.prototype;

      //4.返回值(判断构造函数的返回值是基本类型还是引用类型)
      if (typeof re === 'object' && re !== null || typeof re === "function") {
        return re;
      } else {
        return obj
      }
    }

    const p1 = myNew(Person, "laowang", 18)
    console.log(p1, "p1");
  </script>
</body>

</html>